*** This bug is a duplicate of bug 2083293 ***
https://bugs.launchpad.net/bugs/2083293
** Summary changed:
- Recent Intel CPUs cannot use Skylake to Icelake feature sets on Jammy 22.04
LTS and Noble 24.04 LTS
+ Emeralds rapids CPU cannot use Skylake to Icelake feature sets on Jammy 22.04
LTS and Noble 24.04 LTS
** Description changed:
[Environment]
Tested platform and environments :
* Ubuntu Jammy 22.04 LTS : 8.0.0-1ubuntu7.10 and 10.0.0-2ubuntu8.5~cloud0
(Caracal UCA) with HWE kernel (6.8)
* Ubuntu Noble 24.04 LTS : 10.0.0-2ubuntu8.6
- * Ubuntu Oricular 24.10 : 10.6.0-1ubuntu3.2
+ * Ubuntu Oracular 24.10 : 10.6.0-1ubuntu3.2
Hardware :
* HPE DL360 with Intel Xeon Gold 6542Y
[Issue]
CPU is being recognised as Broadwell, thus missing either Skylake,
Cascadelake, Icelake, SapphireRapids features.
[Impact]
It impacts deployments for any customers using Openstack with Nova and using
any recent Intel CPU like Icelake, Sapphire Rapids, Emerald Rapids, Granite
Rapids and will prevent the user from using any instruction from anything more
recent than Broadwell CPUs.
[Root cause]
For Skylake, Cascadelake, Icelake CPU maps in /usr/share/libvirt/cpu_map/:
- The cpu cannot be recognised because of the missing feature "mpx".
- Upstream has actually a fix for this :
https://gitlab.com/libvirt/libvirt/-/commit/fa5459517848f333743c771e90eb01faeced3dae
+ The cpu cannot be recognised because of the missing feature "mpx".
+ Upstream has actually a fix for this :
https://gitlab.com/libvirt/libvirt/-/commit/fa5459517848f333743c771e90eb01faeced3dae
- Theorically, it should impact IceLake CPUs as well on Jammy 22.04, Noble
24.04 LTS, meaning we have no current Ubuntu LTS to recognise Icelake, Sapphire
Rapids and Emerald Rapids correctly.
- CPU recognition as Icelake-Server-noTSX from both Icelake and SapphireRapids
will work only with libvirt's version from Oricular 24.10.
+ Theorically, it should impact IceLake CPUs as well on Jammy 22.04, Noble
24.04 LTS, meaning we have no current Ubuntu LTS to recognise Icelake, Sapphire
Rapids and Emerald Rapids correctly.
+ CPU recognition as Icelake-Server-noTSX from both Icelake and SapphireRapids
will work only with libvirt's version from Oricular 24.10.
[Potential improvements]
Perform a SRU to backport the fix from upstream with the removed "mpx"
feature to current LTS to allow proper support for recent Intel CPUs
- --> it would at least fix the support for Icelake and allow newer CPUs like
Sapphire Rapids to no end up using a CPU feature set as old as Broadwell
- --> this is confirmed to work with Ubuntu 24.10 but is not a LTS release and
viaable for production/customers environments.
+ --> it would at least fix the support for Icelake and allow newer CPUs like
Sapphire Rapids to no end up using a CPU feature set as old as Broadwell
+ --> this is confirmed to work with Ubuntu 24.10 but is not a LTS release and
viaable for production/customers environments.
** Description changed:
[Environment]
+
Tested platform and environments :
* Ubuntu Jammy 22.04 LTS : 8.0.0-1ubuntu7.10 and 10.0.0-2ubuntu8.5~cloud0
(Caracal UCA) with HWE kernel (6.8)
* Ubuntu Noble 24.04 LTS : 10.0.0-2ubuntu8.6
* Ubuntu Oracular 24.10 : 10.6.0-1ubuntu3.2
+
+ Impacted releases:
+ * Ubuntu Jammy 22.04 LTS : 8.0.0-1ubuntu7.10 and 10.0.0-2ubuntu8.5~cloud0
(Caracal UCA) with HWE kernel (6.8)
+ * Ubuntu Noble 24.04 LTS : 10.0.0-2ubuntu8.6
+ (Oracular does have the fix)
Hardware :
* HPE DL360 with Intel Xeon Gold 6542Y
[Issue]
CPU is being recognised as Broadwell, thus missing either Skylake,
Cascadelake, Icelake, SapphireRapids features.
[Impact]
It impacts deployments for any customers using Openstack with Nova and using
any recent Intel CPU like Icelake, Sapphire Rapids, Emerald Rapids, Granite
Rapids and will prevent the user from using any instruction from anything more
recent than Broadwell CPUs.
[Root cause]
For Skylake, Cascadelake, Icelake CPU maps in /usr/share/libvirt/cpu_map/:
The cpu cannot be recognised because of the missing feature "mpx".
Upstream has actually a fix for this :
https://gitlab.com/libvirt/libvirt/-/commit/fa5459517848f333743c771e90eb01faeced3dae
Theorically, it should impact IceLake CPUs as well on Jammy 22.04, Noble
24.04 LTS, meaning we have no current Ubuntu LTS to recognise Icelake, Sapphire
Rapids and Emerald Rapids correctly.
CPU recognition as Icelake-Server-noTSX from both Icelake and SapphireRapids
will work only with libvirt's version from Oricular 24.10.
[Potential improvements]
Perform a SRU to backport the fix from upstream with the removed "mpx"
feature to current LTS to allow proper support for recent Intel CPUs
--> it would at least fix the support for Icelake and allow newer CPUs like
Sapphire Rapids to no end up using a CPU feature set as old as Broadwell
--> this is confirmed to work with Ubuntu 24.10 but is not a LTS release and
viaable for production/customers environments.
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https://bugs.launchpad.net/bugs/2106812
Title:
Emeralds rapids CPU cannot use Skylake to Icelake feature sets on
Jammy 22.04 LTS and Noble 24.04 LTS
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